The present invention relates to a semiconductor device of BGA (Ball Grid Array) structure and a method for fabricating the same and more particularly to a technology advantageously applied to a T-BGA manufacturing using a TAB (Tape Automated Bonding) tape having leads formed on a surface of an insulating film.
As functions of electronic devices become more sophisticated, the number of components incorporated in them tends to increase. There are also increasing demands on the electronic devices for a smaller size and a lighter weight. Portable electronic devices such as mobile information terminals in particular are being pressed for further reductions in size, thickness and weight. To meet this requirement, efforts are being made to make the electronic components including semiconductor devices mounted on electronic devices still smaller in size, thickness and weight.
As package structures that will make for an improved integration of semiconductor devices and for size and weight reductions, there have been known a TGA that uses a TAB (Tape Automated Bonding) tape having leads formed on a surface of an insulating film (T-BGA) and a FBGA (Fine Pitch BGA) using the TAB tape. These package products that use as a printed circuit board a TAB tape having wires formed on a surface of an insulating film such as polyimide resin film (TCP: Tape Carrier Packages) allow for a higher density, more sophisticated functions and an increased number of pins and also have features of excellent electric characteristics.
On the other hand, semiconductor devices suited to three-dimensional mounting, which improves a mounting density by stacking a plurality of semiconductor devices one upon the other, have been proposed (for example in patent reference 1).
A semiconductor device described in JP-A-2001-223297 has a structure in which a semiconductor chip is mounted on one side of an interposer, with electrodes of the semiconductor chip connected to bonding pads through wires. Ball pads connected to the bonding pads are provided with solder balls. Further, the interposer is formed with through-holes on the side opposite the solder balls of the ball pads. The height of the solder balls is greater than the height of an encapsulant resin enclosing the semiconductor chip. As a result, when the semiconductor devices are stacked together, lower ends of the solder balls of the upper layer semiconductor device overlap the ball pads exposed in the through-holes of the lower layer semiconductor device to make electrical connections.
On the other hand, as a semiconductor package for improving a heat dissipation performance as well as reducing the thickness, a structure has been proposed in which a semiconductor chip is situated at a through-hole formed in the printed circuit board, with a first surface of the chip or a second surface opposite the first surface exposed to dissipate heat from the exposed surface (e.g., JP-A-2000-340713).
The applicant of this invention is also developing a semiconductor device suited to a three-dimensional mounting which uses a TAB tape. This semiconductor device has a structure in which the leads protruding into a device hole provided in the TAB tape are connected to electrodes on a semiconductor chip, in which the portions of the leads situated in the holes are connected with bump electrodes to allow for three-dimensional mounting, and in which one surface side of the semiconductor chip is covered with an insulating resin to cover the leads.
In this structure, however, it is found that, during the process of manufacturing a semiconductor device, a tape substrate formed of a TAB tape which serves as a rearrangement printed wiring board may be warped by thermal stresses.
An object of this invention is to provide a thin semiconductor device free from warping and a method of manufacturing the same.
Another object of this invention is to provide a thin semiconductor device free from warping which is suited to three-dimensional mounting and a method of manufacturing the same.
Still another object of this invention is to provide a thin semiconductor device free from warping at low cost.
The above and other objects and novel features of this invention will become apparent from the following description and the accompanying drawings.